Hi All, I have a dual caliber 5 and love it. I am considering using it at practice with my band (right now it stays safley at home) however I went to mess with running some effects through the effects loop and when anything is pluged into the send on the effects loop it completey cuts the signal...well maybe not completely when I am on the clean channel I can very very faintly here my delay ever so slightly. I have seen people talking about modding and I am not opposed to that but I am interested to see if anyone have had this issue?

I am sure I am plugging everthing in the right way I even plugged it in backward just to be sure. Any help would be greatly appreciated.

The first thing I would try is to clean the effects loop jacks. If you have spray contact cleaner, spray it into the send and return and then take your guitar cable and put it in the jack a few times. You could even spray the end of the guitar cable and push it in a few times. Sometimes, the jacks get oxidized from not being used.

I don't have the tube layout handy, but I think V3 is the fx. You could swap a known good tube into that socket and see if it help/fixes your issue.

Thanks Jedi! I'll try those suggestion and see if it helps. I do have some contact cleaner and I'll check the tube schematic to make sure its v-3 and swap it out to test if the contact cleaner doesn't work.

I tried both suggestions and came up short. I looked at the schematic and as far as I can tell it is V3 running the FX loop...It doesn't seem like a common problem. I know people mod these and I'm wondering if the guy who owned it before me botched a mod or something. The only way to find out is too open it up I guess.

It seems weird though. On the clean channel it cuts out completely when I plug into the send. I can switch to the lead channel and get sound but no effects. Is it possibly the potentiometer that controls the mix of the effects loop? Im just shooting in the dark here. I'll probably have to have someone look at it who is more experienced that me or maybe I should call Mesa. Their headquarters is only two towns up from me.

I cracked the amp open and took a look at everything. The mix pot seemed pretty suspect. it was very loose feeling and seems like it could have been damaged by the previous owner. I went ahead and a did a mod I found on this forum to run the fx loop as sieries instead of parallel. It effectively cut off the mix pot completely. I plugged in a delay pedal and everything is working perfectly. I figure I can just setup a system to bypass the effects if I need to.

It was a very simple mod. I removed the two orange wires from the mix pot and removed the shorter one from the jack completely. I then removed the red wire from the mix pot and connected it to the other orange wire that runs back to the board. I then removed the white wire from the mix pot and capped it off.

Thank you Jedi for taking the time to try and help me with this I really appreciate it.

If I end up having issues with my DC-5 loop, I can always do the mod. I had read about the loop mod (or at least one variation of it) but didn't see a reason to do it unless I wanted to experiment. Might be a good idea just to get inside and do it anyway. I never adjust the mix pot. It's been full on since I got the amp.

Quick update: My amp actually stopped working properly a few days after doing the mod I described. The fix was attaching the red wire and the orange wire that goes to the board back to the lug the orange wire came from. Not sure exactly why it fixed the problem but it was a suggested fix and it worked. So be careful with the mod.